1. Field of the Invention
The present invention relates to a disc brake assembly for wheeled vehicles, and more particularly to a pin boot protector in a disc brake assembly of the pin slide type which includes a stationary support member mounted on a vehicle body structure and having at least one support pin fixed thereto, a caliper member slidably supported on the support pin and movable in an axial direction, and a tubular elastic boot arranged in surrounding relationship with the support pin, the caliper member straddling a portion of a rotary brake disc secured for rotation with a road wheel of the vehicle and having a fluid actuator on one side thereof to press the friction pad of an inner brake shoe against one face of the brake disc and a reaction portion on the opposite side thereof to press the friction pad of an outer brake shoe against the other face of the brake disc by reaction force caused by actuation of the fluid actuator.
2. Discussion of the Background
In Japanese Utility Model Early Publications Nos. 56-2431 and 58-79142, there has been proposed such a conventional disc brake assembly of the pin slide type as described above, wherein a cup-shaped rigid protector is arranged to enclose the tubular elastic pin boot for protection of the same. The cylindrical rigid protector, however, is fixed at its one end to either the caliper member or the stationary support member and opens outwardly at its other end because of the lack of elasticity thereof. The cup-shaped rigid protector is also formed short in length to avoid interference with the stationary support member or the caliper member when both friction pads have been defaced so as to cause displacement of the caliper member. For these reasons, the cup-shaped rigid protector is ineffective to prevent entry of foreign particles such as sand, mud and the like therein. If the foreign particles are accumulated within the cup-shaped rigid protector, the tubular elastic boot will be damaged by friction caused by the accumulated foreign particles during sliding movement of the caliper member on the support pin.